Argentine prosecutor Alberto Nisman (51), who accused President Cristina Kirchner of obstructing a probe into a 1994 Jewish center bombing, was found shot dead Monday, just hours before he was due to testify at a congressional hearing.
Nisman was found dead overnight in his apartment in the trendy Puerto Madero neighborhood of the capital.
"I can confirm that a .22-caliber handgun was found beside the body," prosecutor Viviana Fein said. "Death is due to gunshot." Given the timing, and threats he was revealed to have received, there is a high suspicion of a framed suicide.
Authorities said Nisman had been found by his mother in the bathroom of his 13th floor apartment after his security detail was unable to contact him.
Nisman had since 2004 been investigating the 1994 van bombing of the building of the Argentine Jewish Charities Federation, or AMIA. The bombing left 85 people dead and 300 others injured in the worst attack of its kind in the South American country.
Nisman had last week asked for an investigation into possible obstruction by Kirchner and was due to speak at a Congressional hearing Monday to provide evidence of his assertions.
The prosecutor has accused Iran of being behind the attack and said Kirchner hampered the inquiry to curry favor with the Islamic republic. The government has categorically denied the accusations.
Nisman had also accused former president Carlos Menem (1989-'99) of helping obstruct an investigation into the bombing, which has never been solved.
With his request last week for an investigation, Nisman said in an interview that the investigation was "likely to kill me." In the interview he added "from today my life has changed. I told my daughter she is likely to hear awful things about her father."
Since 2006, Argentine courts have demanded the extradition of eight Iranians, including former president Akbar Hashemi Rafsanjani, former defense minister Ahmad Vahidi and Mohsen Rabbani, Iran's former cultural attache in Buenos Aires.
Likewise, Iranian President Hassan Rouhani was found to have been on the special Iranian government committee that plotted the 1994 bombing, according to an indictment by the Argentine government prosecutor investigating the case.
Argentina charges that Hezbollah, the Lebanese Shi'ite terrorist movement and Iranian proxy, carried out the attack under orders from Iran, which Tehran denies.
Nisman had said he had phone recordings that show the Kirchner government and Argentine authorities had bowed to Iranian demands after the Islamic republic dangled lucrative commercial contracts.
Nisman was supposed to present proof of his allegations that Kirchner and Foreign Minister Hector Timerman had a "plan of impunity" to "protect the Iranian fugitives."
In addition to his complaint, Nisman had ordered the freezing of assets worth some $23 million of Kirchner, Timerman and other officials.
Jewish community members had cautiously welcomed Nisman's complaint, but also requested he make public evidence to back up his assertions.
Opposition lawmaker Patricia Bullrich said she was shocked by Nisman's death, calling it "a grave affront to the country's institutions."
Bullrich said she'd spoken to Nisman on the phone on Saturday on three occasions and he'd said that he'd received several threats.
In 2013, Argentina's congress approved, at the request of the executive branch, an agreement with Tehran to form a truth commission to investigate the bombing, consisting of five members who don't come from either Argentina or Iran.
It also authorized an Argentine judge to travel to Iran to question the former officials accused of involvement.
The Jewish center bombing came two years after an attack against the Israeli embassy in Buenos Aires that killed 29 people.
In January 2014, Argentina accused Israel of concealing information about the attacks after a former Israeli ambassador to Argentina suggested that those responsible had been killed by Israeli security forces.
Argentina's Jewish population of about 300,000 people is the largest in Latin America.
AFP contributed to this report.